The ratings for The Flight Attendant from 2020 are consistently decent, with most episodes falling between 7.1 and 7.8. This would indicate that the show maintains a certain level of quality throughout both seasons. Based on the ratings provided, the show does not seem to significantly improve or worsen as it progresses. Therefore, it can be said that The Flight Attendant maintains a consistent level of quality from start to finish. As for the bingeable rating, it would be around 60 as the show seems to offer a decent level of entertainment without any significant ups or downs in quality.